Hyaloclastite, sideromelane or tachylite pozzolan-based geopolymer cement and concrete and method of making and using same

ABSTRACT

The invention comprises a cementitious material comprising a natural pozzolan selected from hyaloclastite, sideromelane or tachylite, wherein the natural pozzolan has a volume-based mean particle size of less than or equal to 40 μm. The cementitious material also comprising an aqueous alkaline activating solution suitable for forming a geopolymer. A method making a cementitious material is also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.16/049,399 filed Jul. 30, 2018, now U.S. Pat. No. 10,745,321, which is acontinuation of application Ser. No. 15/817,469 filed Nov. 20, 2017, nowU.S. Pat. No. 10,047,005, which is a continuation-in-part of applicationSer. No. 15/595,411 filed May 15, 2017, now U.S. Pat. No. 9,822,037 anda continuation-in-part of application Ser. No. 15/595,430 filed May 15,2017, now U.S. Pat. No. 9,828,289.

FIELD OF THE INVENTION

The present invention generally relates to a natural pozzolan. Moreparticularly, the present invention relates to a cementitious materialcontaining hyaloclastite, sideromelane or tachylite (also spelled“tachylyte”). The present invention further relates to concrete ormortar containing hyaloclastite, sideromelane or tachylite or acementitious material that contains hyaloclastite, sideromelane ortachylite. The present invention also relates to a method of making ahyaloclastite-based cementitious material, a sideromelane-basedcementitious material or a tachylite-based cementitious material. Thepresent invention further relates to a method a making concrete with ahydraulic cement and a hyaloclastite-based pozzolan, asideromelane-based pozzolan or a tachylite-based pozzolan. The presentinvention further relates to a method of making concrete or mortar withportland cement and a hyaloclastite-based pozzolan, a sideromelane-basedpozzolan or a tachylite-based pozzolan. The present invention alsorelates to a method of making concrete comprising a cementitiousmaterial based on hyaloclastite, sideromelane or tachylite. In addition,the present invention relates to a method of curing concrete comprisinga hyaloclastite-based pozzolan a sideromelane-based pozzolan or atachylite-based pozzolan or a hyaloclastite-based cementitious material,a sideromelane-based cementitious material or a tachylite-basedcementitious material.

BACKGROUND OF THE INVENTION

Concrete dates back at least to Roman times. The invention of concreteallowed the Romans to construct building designs, such as arches, vaultsand domes, that would not have been possible without the use ofconcrete. Roman concrete, or opus caementicium, was made from ahydraulic mortar and aggregate or pumice. The hydraulic mortar was madefrom either quicklime, gypsum or pozzolana. Quick lime, also known asburnt lime, is calcium oxide; gypsum is calcium sulfate dihydrate andpozzolana is a fine, sandy volcanic ash (with properties that were firstdiscovered in Pozzuoli, Italy). The concrete made with volcanic ash asthe pozzolanic agent was slow to set and gain strength. Most likely theconcrete was build up in multiple layers on forms that had to stay inplace for a very long time. Although the concrete was slow to set andgain strength, over long periods of time it achieved great strength andwas extremely durable. There are still Roman concrete structuresstanding today as a testimony to the quality of the concrete producedover 2000 years ago.

Modern concrete is composed of one or more hydraulic cements, coarseaggregates, and fine aggregates. Optionally, modern concrete can includeother cementitious materials, inert fillers, property modifyingadmixtures and coloring agents. The hydraulic cement is typicallyportland cement. Other cementitious materials include fly ash, slagcement and other known natural pozzolanic materials. The term “pozzolan”is defined in ACI 116R as, “ . . . a siliceous or siliceous andaluminous material, which in itself possesses little or no cementitiousvalue but will, in finely divided form and in the presence of moisture,chemically react with calcium hydroxide at ordinary temperatures to formcompounds possessing cementitious properties.”

Portland cement is the most commonly used hydraulic cement in use aroundthe world today. Portland cement is typically made from limestone.Concrete or mortar made with portland cement sets relatively quickly andgains relatively high compressive strength in a relatively short time.Although significant improvements have been made to the process andefficiency of portland cement manufacturing, it is still a relativelyexpensive and highly polluting industrial process.

Fly ash is a by-product of the combustion of pulverized coal in electricpower generation plants. When the pulverized coal is ignited in acombustion chamber, the carbon and volatile materials are burned off.When mixed with lime and water, fly ash forms a compound similar toportland cement. Two classifications of fly ash are produced accordingto the type of coal from which the fly ash is derived. Class F fly ashis normally produced from burning anthracite or bituminous coal thatmeets applicable requirements. This class of fly ash has pozzolanicproperties and will have minimum amounts of silica dioxide, aluminumoxide and iron oxide of 70%. Class F fly ash is generally used inhydraulic cement at dosage rates of 15% to 30% by weight, with thebalance being portland cement. Class C fly ash is normally produced fromlignite or subbituminous coal that meets applicable requirements. Thisclass of fly ash, in addition to pozzolanic properties, also has somecementitious properties. Class C fly ash is used in hydraulic cement atdosage rates of 15% to 40% by weight, with the balance being portlandcement.

Recently, the U.S. concrete industry has used an average of 15 milliontons of fly ash at an average portland cement replacement ratio ofapproximately 16% by weight. Since fly ash is a by-product from theelectric power generating industry, the variable properties of fly ashhave always been a major concern to the end users in the concreteindustry. Traditionally, wet scrubbers and flue gas desulfurization(“FGD”) systems have been used to control power plant SO₂ and SO₃emissions. The residue from such systems consists of a mixture ofcalcium sulfite, sulphate, and fly ash in water. In using sodium-basedreagents to reduce harmful emissions from the flue gas, sodium sulfiteand sulfate are formed. These solid reaction products are incorporatedin a particle stream and collected with the fly ash in particulatecontrol devices. There is the potential for the sodium-based reagent toreact with other components of the gas phases and with ash particulatesin the flue gas and in the particulate control device. All of theproducts of these reactions have the potential to impact the resultingfly ash. Anecdotal evidence has shown that the fly ash that containssodium-based components has unpredictable and deleterious effect inconcrete. Consequently, the concrete industry is at great risk of usinga product that is unpredictable in its performance. Coupled with theclosure of many coal-fired power plants, resulting in less availabilityof fly ash, the concrete industry is facing a dramatic shortage of afamiliar pozzolan.

Known natural pozzolans can be used in concrete to replace the growingshortage of fly ash. However, known natural pozzolan deposits arelimited and generally are far from construction markets. Naturalpozzolans can be raw or processed. ASTM C-618 defined Class N naturalpozzolans as, “Raw or calcined natural pozzolans that comply with theapplicable requirements for the class as given herein, such as somediatomaceous earth; opaline chert and shales; tuffs and volcanic ashesor pumicites, any of which may or may not be processed by calcination;and various materials requiring calcination to induce satisfactoryproperties, such as some clays and shales.”

Other known natural pozzolans include Santorin earth, Pozzolana,Trachyte, Rhenish trass, Gaize, volcanic tuffs, pumicites, diatomaceousearth, and opaline shales, rice husk ash and metakaolin. Santorin earthis produced from a natural deposit of volcanic ash of daciticcomposition on the island of Thera in the Agean Sea, also known asSantorin, which was formed about 1600-1500 B.C. after a tremendousexplosive volcanic eruption (Marinatos 1972). Pozzolana is produced froma deposit of pumice ash or tuff comprised of trachyte found near Naplesand Segni in Italy. Pozzolana is a product of an explosive volcaniceruption in 79 A.D. at Mount Vesuvius, which engulfed Herculaneum,Pompeii, and other towns along the bay of Naples. The deposit nearPozzuoli is the source of the term “pozzolan” given to all materialshaving similar properties. Similar tuffs of lower silica content havebeen used for centuries and are found in the vicinity of Rome. In theUnited States, volcanic tuffs and pumicites, diatomaceous earth, andopaline shales are found principally in Oklahoma, Nevada, Arizona, andCalifornia. Rice husk ash (“RHA”) is produced from rice husks, which arethe shells produced during the dehusking of rice. Rice husks areapproximately 50% cellulose, 30% lignin, and 20% silica. Metakaolin(Al₂O₃:2SiO₂) is a natural pozzolan produced by heatingkaolin-containing clays over a temperature range of about 600 to 900° C.(1100 to 1650° F.) above which it recrystallizes, rendering it mullite(Al₆Si₂O₁₃) or spinel (MgAl₂O₄) and amorphous silica (Murat, Ambroise,and Pera 1985). The reactivity of metakaolin is dependent upon theamount of kaolinite contained in the original clay material. The use ofmetakaolin as a pozzolanic mineral admixture has been known for manyyears, but has grown rapidly since approximately 1985.

Natural pozzolans were investigated in this country by Bates, Phillipsand Wig as early as 1908 (Bates, Phillips and Wig 1912) and later byPrice (1975), Meissner (1950), Mielenz, Witte, and Glantz (1950), Davis(1950), and others. They showed that concretes containing pozzolanicmaterials exhibited certain desirable properties such as lower cost,lower temperature rise, and improved workability. According to Price(1975), an example of the first large-scale use of portland-pozzolancement, composed of equal parts of Portland cement and a rhyoliticpumicite, is the Los Angeles aqueduct in 1910-1912. Natural pozzolans bytheir very definition have high silica or alumina and silica contenteither in a raw or calcined form.

Generally fly ash has the advantage that it can reduce water demand ofthe cementitious matrix. This reduces plastic shrinkage and allows forbetter workability. Generally, known natural pozzolans and silica fumeincrease water demand in the cementitious matrix; in some cases as highas 110%-115% that of portland cement. Greater water demand createsundesirable concrete properties such as lower strength development andgreater plastic shrinkage. It is desired that pozzolans have a waterdemand that is lower than or equal to portland cement. However, this isan extremely rare occurrence for known natural pozzolans.

The alkali-silica reaction (“ASR”), more commonly known as “concretecancer”, is a reaction that occurs over time in concrete between thehighly alkaline cement paste and the reactive non-crystalline(amorphous) silica found in many common aggregates, provided there issufficient moisture present. This reaction causes the expansion of thealtered aggregate by the formation of a soluble and viscous gel ofsodium silicate (Na₂SiO₃.n H₂O, also noted Na₂H₂SiO₄.n H₂O, or N—S—H(sodium silicate hydrate), depending on the adopted convention). Thishygroscopic gel swells and increases in volume when absorbing water. Theswelling gel exerts an expansive pressure inside the siliceousaggregate, causing spalling and loss of strength of the concrete,finally leading to its failure. ASR can cause serious cracking inconcrete, resulting in critical structural problems that can even forcethe demolition of a particular structure.

Therefore, it would be desirable to have a natural pozzolan that doesnot need to be calcined to render it active. It would also be desirableto have a natural pozzolan that has a water demand less than or equal toportland cement. It would also be desirable to have a natural pozzolanwith properties as good as or better than fly ash. It would also bedesirable to have a natural pozzolan that reduces ASR in concrete. Itwould be desirable to have a natural pozzolan that has ASR mitigationproperties better than or equal to portland cement. It would also bedesirable to have a natural pozzolan with similar specific gravity asportland cement that can replace portland cement on a one-to-one basis.It would also be desirable to have a natural pozzolan that produce aconcrete with relatively rapid setting and strength gaining properties.It would also be desirable to have a natural pozzolan that when combinedwith portland cement produces a concrete with an ultimate compressivestrength greater than or equal to straight portland cement-basedconcrete.

SUMMARY OF THE INVENTION

The present invention satisfies the foregoing needs by providing anatural pozzolan that has improved properties and lower water demandthan known natural pozzolans.

In one disclosed embodiment, the present invention comprises acementitious material. The cementitious material comprises a naturalpozzolan selected from hyaloclastite, sideromelane or tachylite, whereinthe natural pozzolan has a volume-based mean particle size of less thanor equal to 40 The cementitious material also comprising an aqueousalkaline activating solution suitable for forming a geopolymer.

In another disclosed embodiment, the present invention comprises acementitious-based material. The cementitious-based material comprisesaggregate, hyaloclastite having a volume-based mean particle size ofless than or equal to approximately 40 μm and an alkaline activatingsolution comprising sodium hydroxide or potassium hydroxide and water.

In yet another disclosed embodiment, the present invention comprises amethod of making a cementitious material. The method comprises combininga natural pozzolan selected from hyaloclastite, sideromelane, tachyliteor combinations or mixtures thereof, wherein the natural pozzolan has avolume-based mean particle size of less than or equal to approximately40 μm and an aqueous alkaline activating solution suitable for forming ageopolymer.

In another disclosed embodiment, the present invention comprises amethod. The method comprises placing in a form or a mold a cementitiouscomposition comprising aggregate and a geopolymer, wherein thegeopolymer comprises a natural pozzolan selected from hyaloclastite,sideromelane or tachylite, wherein the natural pozzolan has avolume-based mean particle size of less than or equal to 40 μm and anaqueous alkaline activating solution suitable for forming a geopolymer.

Accordingly, it is an object of the present invention to provide animproved concrete or mortar.

Another object of the present invention is to provide an improvedcementitious material.

A further object of the present invention is to provide an improvedgeopolymer.

Yet another object of the present invention is to provide an improvedgeopolymer cement.

Another object of the present invention is to provide an improvedgeopolymer cement concrete.

Another object of the present invention is to provide an improvednatural pozzolan.

Another object of the present invention is to provide a natural pozzolanselected from hyaloclastite, sideromelane, tachylite or combinations ormixtures thereof.

These and other objects, features and advantages of the presentinvention will become apparent after a review of the following detaileddescription of the disclosed embodiments and the appended claims.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS

Hyaloclastite is a tuff-like breccia typically rich in black volcanicglass, formed during volcanic eruptions under water, under ice or wheresubaerial flows reach the sea or other bodies of water. It has theappearance of angular fragments sized from approximately a millimeter toa few centimeters. Larger fragments can be found up to the size ofpillow lava as well. Several minerals are found in hyaloclastite massesincluding, but not limited to, sideromelane, tachylite, palagonite,olivine, pyroxene, magnetite, quartz, hornblende, biotite, hypersthene,feldspathoids, plagioclase, calcite and others. Fragmentation can occurby both an explosive eruption process or by an essentially nonexplosiveprocess associated with the spalling of pillow basalt rinds by thermalshock or chill shattering of molten lava. The water-quenched basaltglass is called sideromelane, a pure variety of glass that istransparent, and lacks the very small iron-oxide crystals found in themore common opaque variety of basalt glass called tachylite. Inhyaloclastite, these glassy fragments are typically surrounded by amatrix of yellow-to-brown palagonite, a wax-like substance that formsfrom the hydration and alteration of the sideromelane and otherminerals. Depending on the type of lava, the rate of cooling and theamount of lava fragmentation, the particle of the volcanic glass(sideromelane) can be mixed with other volcanic rocks or crystallineminerals, such as olivine, pyroxene, magnetite, quartz, plagioclase,calcite and others.

Hyaloclastite is usually found within or adjacent subglacial volcanoes,such as tuyas, which is a type of distinctive, flat-topped, steep-sidedvolcano formed when lava erupts under or through a thick glacier or icesheet. Hyaloclastite ridges are also called tindars and subglacialmounds are called tuyas or mobergs. They have been formed by subglacialvolcanic eruptions during the last glacial period. A subglacial mound isa type of subglacial volcano. This type of volcano forms when lavaerupts beneath a thick glacier or ice sheet. The magma forming thesevolcanoes was not hot enough to melt a vertical pipe through theoverlying glacial ice, instead forming hyaloclastite and pillow lavadeep beneath the glacial ice field. Once the glacier retreated, thesubglacial volcano was revealed, with a unique shape as a result of itsconfinement within the glacial ice. Subglacial volcanoes are somewhatrare worldwide, being confined to regions that were formerly covered bycontinental ice sheets and also had active volcanism during the sameperiod. Currently, volcanic eruptions under existing glaciers may createhyaloclastite as well. Hyaloclastite tuff-like breccia is a pyroclasticrock comprised of glassy juvenile clasts contained in a fine-grainedmatrix dominated by glassy shards. Hyaloclastite breccias are typicallyproducts of phreatomagmatic eruptions in particular associated with theeruption of magmas into bodies of water and form by fragmentation ofchilled magma. They are often formed from basaltic magmas and areassociated with pillow lavas and sheet flows. In addition, any othertype of lava, such as intermediate, andesitic, dacitic and rhyolitic,can form hyaloclastite under similar rapid cooling or quenchingconditions.

In lava deltas, hyaloclastite forms the main constituent of foresetsformed ahead of the expanding delta. The foresets fill in the seabedtopography, eventually building up to sea level, allowing the subaerialflow to move forward until it reaches the sea again.

At mid-ocean ridges, tectonic plates diverge, creating fissures on theocean floor. Along these fissures underwater volcanoes erupt forming seamounds that in some places can reach the surface of the water. As thelava erupts underwater, it can be rapidly quenched thereby creatinghyaloclastite. This is an active process especially at hot spots aroundthe world. These hot spots are an important cause of island formation.These islands are a prime sources of hyaloclastite formation.

Volcanic lava eruptions in Hawaii that spill in the ocean are alsorapidly quenched and fragmented thus producing hyaloclastite. The rapidcooling and quenching prevents or reduces lava crystallization thushyaloclastite may have a significant amorphous make up.

Basalt is an aphanitic (fine-grained) igneous rock with generally 43% to53% silica (SiO₂) containing essentially calcic plagioclase feldspar andpyroxene (usually Augite), with or without olivine. Intermediate basalthas generally between 53% to 57% silica (SiO₂) content. Basalts can alsocontain quartz, hornblende, biotite, hypersthene (an orthopyroxene) andfeldspathoids. Basalts are often porphyritic and can contain mantlexenoliths. Basalt is distinguished from pyroxene andesite by its morecalcic plagioclase. There are two main chemical subtypes of basalt:tholeiites which are silica saturated to oversaturated and alkalibasalts that are silica under saturated. Tholeiitic basalt dominates theupper layers of oceanic crust and oceanic islands, alkali basalts arecommon on oceanic islands and in continental magmatism. Basalts canoccur as both shallow hypabyssal intrusions or as lava flows. Theaverage density basalt is approximately 3.0 gm/cm³.

Andesite is an abundant igneous (volcanic) rock of intermediatecomposition, with aphanitic to porphyritic texture. In a general sense,it is an intermediate type between basalt and dacite, and ranges from57% to 63% silicon dioxide (SiO₂). The mineral assemblage is typicallydominated by plagioclase plus pyroxene or hornblende. Magnetite, zircon,apatite, ilmenite, biotite, and garnet are common accessory minerals.Alkali feldspar may be present in minor amounts.

Dacite is an igneous, volcanic rock with an aphanitic to porphyritictexture and is intermediate in composition between andesite and rhyoliteand ranges from 63% to 69% silicon dioxide (SiO₂). It consists mostly ofplagioclase feldspar with biotite, hornblende, and pyroxene (augiteand/or enstatite). It has quartz as rounded, corroded phenocrysts, or asan element of the ground-mass. The plagioclase ranges from oligoclase toandesine and labradorite. Sanidine occurs, although in smallproportions, in some dacites, and when abundant gives rise to rocks thatform transitions to the rhyolites. The groundmass of these rocks iscomposed of plagioclase and quartz.

Rhyolite is an igneous (volcanic) rock of felsic (silica-rich)composition, typically greater than 69% SiO₂. It may have a texture fromglassy to aphanitic to porphyritic. The mineral assemblage is usuallyquartz, sanidine and plagioclase. Biotite and hornblende are commonaccessory minerals.

Hyaloclastite can be classified based on the amount of silica contentas: basaltic (less than 53% by weight SiO₂), intermediate (approx.53-57% by weight SiO₂), or silicic such as andesitic (approximately57-63% by weight SiO₂), dacitic (approximately by weight 63-69% byweight SiO₂), or rhyolitic (greater than 69% by weight SiO₂). Basaltichyaloclastite can be classified based on alkalinity level as tholeiitic,intermediate and alkaline.

As used herein, the term “hyaloclastite” shall mean hyaloclastite fromany and all sources; i.e., all hyaloclastites irrespective of themineral source from which it is derived.

Hyaloclastite, sideromelane or tachylite deposits can be found in manyplaces throughout the world including, but not limited to, Alaska, NewMexico, Michigan, British Columbia, Hawaii, Iceland, throughout theworld oceans on seamounts and on oceanic islands formed at magmatic arcsand tectonic plate rifts by volcanic activity, such as the mid-Atlanticridge, and others.

In one disclosed embodiment, the present invention compriseshyaloclastite in powder form. The particle size of the hyaloclastitepowder is sufficiently small such that the hyaloclastite powder haspozzolanic properties. The hyaloclastite powder preferably has avolume-based mean particle size of less than or equal to approximately40 μm, more preferably less than or equal to 20 most preferably lessthan or equal to 15 μm, especially less than or equal to 10 moreespecially less than or equal to 5 μm. The smaller the particle size forthe hyaloclastite powder the better. However, there are economic limitsfor grinding rock to small particle sizes. Those limits are well knownby those skilled in the art. The hyaloclastite powder preferably has aBlaine value of approximately 1,500 to approximately 10,000, morepreferably approximately 3,500 to approximately 10,000, most preferablyapproximately 4,500 to approximately 10,000, especially approximately6,000 to approximately 10,000. The hyaloclastite powder preferably has aBlaine value of greater than or equal to approximately 10,000. Theforegoing ranges include all of the intermediate values.

In another disclosed embodiment, the present invention comprisessideromelane in powder form. The particle size of the sideromelanepowder is sufficiently small such that the sideromelane powder haspozzolanic properties. The sideromelane powder preferably has avolume-based mean particle size of less than or equal to approximately40 μm, more preferably less than or equal to 20 μm, most preferably lessthan or equal to 15 μm, especially less than or equal to 10 μm, moreespecially less than or equal to 5 μm. The smaller the particle size forthe sideromelane powder the better. However, there are economic limitsfor grinding rock to small particle sizes. Those limits are well knownby those skilled in the art. The sideromelane powder preferably has aBlaine value of approximately 1,500 to approximately 10,000, morepreferably approximately 3,500 to approximately 10,000, most preferablyapproximately 4,500 to approximately 10,000, especially approximately6,000 to approximately 10,000. The sideromelane powder preferably has aBlaine value of greater than or equal to approximately 10,000. Theforegoing ranges include all of the intermediate values.

In another disclosed embodiment, the present invention comprisestachylite in powder form. The particle size of the tachylite powder issufficiently small such that the tachylite powder has pozzolanicproperties. The tachylite powder preferably has a volume-based meanparticle size of less than or equal to approximately 40 μm, morepreferably less than or equal to 20 μm, most preferably less than orequal to 15 μm, especially less than or equal to 10 μm, more especiallyless than or equal to 5 μm. The smaller the particle size for thetachylite powder the better. However, there are economic limits forgrinding rock to small particle sizes. Those limits are well known bythose skilled in the art. The tachylite powder preferably has a Blainevalue of approximately 1,500 to approximately 10,000, more preferablyapproximately 3,500 to approximately 10,000, most preferablyapproximately 4,500 to approximately 10,000, especially approximately6,000 to approximately 10,000. The tachylite powder preferably has aBlaine value of greater than or equal to approximately 10,000. Theforegoing ranges include all of the intermediate values.

To achieve the desired particles size, the hyaloclastite, sideromelaneor tachylite rock can be ground using conventional rock grinding meansincluding, but not limited to, a ball mill, a roll mill or a plate mill.A particle size classifier can be used in conjunction with the mill toachieve the desired particle size. Equipment for grinding andclassifying hyaloclastite to the desired particle size is commerciallyavailable from, for example, F. L. Smidth, Bethlehem, Pa.; Metso,Helsinki, Finland and others. The ground hyaloclastite, sideromelane ortachylite powder is then preferably classified by screening the powderwith a 325-mesh screen or sieve. Preferably approximately 80% by volumeof the hyaloclastite, sideromelane or tachylite powder passes through a325-mesh screen, more preferably approximately 85% by volume of thehyaloclastite, sideromelane or tachylite powder passes through a325-mesh screen, most preferably approximately 90% by volume of thehyaloclastite, sideromelane or tachylite powder passes through a325-mesh screen, especially approximately 95% by volume of thehyaloclastite, sideromelane or tachylite powder passes through a325-mesh screen and more especially approximately 100% by volume of thehyaloclastite, sideromelane or tachylite powder passes through a325-mesh screen. Preferably approximately 80% to approximately 100% byvolume of the hyaloclastite, sideromelane or tachylite powder passesthrough a 325-mesh screen, more preferably approximately 90% toapproximately 100% by volume of the hyaloclastite, sideromelane ortachylite powder passes through a 325-mesh screen, most preferablyapproximately 95% to approximately 100% by volume of the hyaloclastite,sideromelane or tachylite powder passes through a 325-mesh screen,especially approximately 100% by volume of the hyaloclastite,sideromelane or tachylite powder passes through a 325-mesh screen. Theforegoing ranges include all of the intermediate values. Preferably amaximum of 34% by volume of the hyaloclastite, sideromelane or tachylitepowder is retained on the 325-mesh screen, more preferably a maximum ofapproximately 20% by volume of the hyaloclastite, sideromelane ortachylite powder is retained on the 325-mesh screen, most preferably amaximum of approximately 10% by volume of the hyaloclastite,sideromelane or tachylite powder is retained on the 325-mesh screen,especially a maximum of approximately 5% by volume of the hyaloclastite,sideromelane or tachylite powder is retained on the 325-mesh screen,more especially approximately 0% by volume of the hyaloclastite,sideromelane or tachylite powder is retained on the 325-mesh screen. Theforegoing percentages include all of the intermediate values.

In another disclosed embodiment, the hyaloclastite, sideromelane ortachylite rock can be interground with hydraulic cement clinker. Forexample, hyaloclastite, sideromelane or tachylite rock can beinterground with portland cement clinker or slag cement clinker. That ishyaloclastite, sideromelane or tachylite rock and portland cementclinker can be combined and ground at the same time with the sameequipment.

In one disclosed embodiment of the present invention, the hyaloclastite,sideromelane or tachylite preferably has a chemical composition ofapproximately 43% to approximately 57% by weight SiO₂, approximately 5%to approximately 20% by weight Al₂O₃, approximately 8% to approximately15% by weight Fe₂O₃, approximately 5% to approximately 15% by weightCaO, approximately 5% to approximately 15% by weight MgO, less than orequal to approximately 3% by weight Na₂O. In addition to the foregoing,other compounds can be present in small amounts, such as K₂O, TiO₂,P₂O₅, MnO, various metals, rare earth trace elements and otherunidentified elements. When combined, these other compounds representless than 10% by weight of the total chemical composition of thehyaloclastite mineral.

In another disclosed embodiment, the hyaloclastite, sideromelane ortachylite in accordance with the present invention preferably has adensity or specific gravity of approximately 2.8 to approximately 3.1.

Hyaloclastite, sideromelane or tachylite in accordance with the presentinvention can be in crystalline or amorphous (glassy) form and isusually found as a combination of both in varying proportions.Preferably, the hyaloclastite, sideromelane or tachylite in accordancewith the present invention comprises approximately 0% to 99% by weightamorphous form, more preferably approximately 10% to approximately 80%by weight amorphous form, most preferably approximately 20% toapproximately 60% by weight amorphous form, especially approximately 30%to approximately 50% by weight amorphous form. The crystalline portionof hyaloclastite, sideromelane or tachylite preferably comprisesapproximately 3% to approximately 20% by weight olivine, approximately5% to approximately 40% by weight clinopyroxene, approximately 5% toapproximately 60% by weight plagioclase, and approximately 0% toapproximately 10% (or less than 10%) by weight other minerals including,but not limited to, magnetite, UlvoSpinel, quartz, feldspar, pyrite,illite, hematite, chlorite, calcite, hornblende, biotite, hypersthene(an orthopyroxene), feldspathoids sulfides, metals, rare earth minerals,other unidentified minerals and combinations thereof. The foregoingranges include all of the intermediate values.

Hyaloclastite, sideromelane, tachylite or combinations or mixturesthereof in accordance with the present invention can be used as asupplementary cementitious material in concrete or mortar mixes. Inaddition, hyaloclastite, sideromelane or tachylite in accordance withthe present invention when mixed with cement may improve the cementnucleation process thereby improving the cement hydration process.Hyaloclastite, sideromelane or tachylite in finer particles generallyyields shorter set times and accelerates hydration in blended cements.Finer particle size hyaloclastite, sideromelane or tachylite increasesthe rate of hydration heat development and early-age compressivestrength in portland cement. This acceleration may be attributable tothe hyaloclastite sideromelane or tachylite particle size (nucleationsites), its crystalline make-up and/or chemical composition.Hyaloclastite, sideromelane or tachylite in accordance with the presentinvention can be used in combination with any hydraulic cement, such asportland cement. Other hydraulic cements include, but are not limitedto, blast granulated slag cement, calcium aluminate cement, belitecement (dicalcium silicate), phosphate cements and others. Also,hyaloclastite, sideromelane or tachylite in accordance with the presentinvention by itself can be blended with lime to form a cementitiousmaterial. In one disclosed embodiment, blended cementitious material forcement or mortar preferably comprises approximately 10% to approximately90% by weight hydraulic cement and approximately 10% to approximately90% by weight hyaloclastite, sideromelane, tachylite or mixtures thereofin accordance with the present invention, more preferably approximately20% to approximately 80% by weight hydraulic cement and approximately20% to approximately 80% by weight hyaloclastite, sideromelane,tachylite or mixtures thereof in accordance with the present invention,most preferably approximately 30% to approximately 70% by weighthydraulic cement and approximately 30% to approximately 70% by weighthyaloclastite, sideromelane, tachylite or mixtures thereof in accordancewith the present invention, especially approximately 40% toapproximately 60% by weight hydraulic cement and approximately 40% toapproximately 60% by weight hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention, moreespecially approximately 50% by weight hydraulic cement andapproximately 50% by weight hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention, and mostespecially approximately 70% by weight hydraulic cement andapproximately 30% by weight hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention. In anotherdisclosed embodiment of the present invention, cementitious material forconcrete or mortar preferably comprises approximately 50% toapproximately 90% by weight hydraulic cement and approximately 10% toapproximately 50% by weight hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention. The foregoingranges include all of the intermediate values.

The present invention can be used with conventional concrete mixes.Specifically, a concrete mix in accordance with the present inventioncomprises cementitious material, aggregate and water sufficient tohydrate the cementitious material. The cementitious material comprises ahydraulic cement and hyaloclastite, sideromelane, tachylite or mixturesthereof in accordance with the present invention. The amount ofcementitious material used relative to the total weight of the concretevaries depending on the application and/or the strength of the concretedesired. Generally speaking, however, the cementitious materialcomprises approximately 6% to approximately 30% by weight of the totalweight of the concrete, exclusive of the water, or 200 lbs/yd³ (91kg/m³) of cement to 1,200 lbs/yd³ (710 kg/m³) of cement. In ultra highperformance concrete, the cementitious material may exceed 25%-30% byweight of the total weight of the concrete. The water-to-cement ratio byweight is usually approximately 0.25 to approximately 0.7. Relativelylow water-to-cement materials ratios by weight lead to higher strengthbut lower workability, while relatively high water-to-cement materialsratios by weight lead to lower strength, but better workability. Forhigh performance concrete and ultra high performance concrete, lowerwater-to-cement ratios are used, such as approximately 0.20 toapproximately 0.25. Aggregate usually comprises 70% to 80% by volume ofthe concrete. In ultra high performance concrete, the aggregate can beless than 70% of the concrete by volume. However, the relative amountsof cementitious material to aggregate to water are not a criticalfeature of the present invention; conventional amounts can be used.Nevertheless, sufficient cementitious material should be used to produceconcrete with an ultimate compressive strength of at least 1,000 psi,preferably at least 2,000 psi, more preferably at least 3,000 psi, mostpreferably at least 4,000 psi, especially up to about 10,000 psi ormore. In particular, ultra high performance concrete, concrete panels orconcrete elements with compressive strengths of over 20,000 psi can becast and cured using the present invention.

The aggregate used in the concrete in accordance with the presentinvention is not critical and can be any aggregate typically used inconcrete. The aggregate that is used in the concrete depends on theapplication and/or the strength of the concrete desired. Such aggregateincludes, but is not limited to, fine aggregate, medium aggregate,coarse aggregate, sand, gravel, crushed stone, lightweight aggregate,recycled aggregate, such as from construction, demolition and excavationwaste, and mixtures and combinations thereof.

The reinforcement of the concrete in accordance with the presentinvention is not a critical aspect of the present invention, and, thus,any type of reinforcement required by design requirements can be used.Such types of concrete reinforcement include, but are not limited to,deformed steel bars, cables, post tensioned cables, pre-stressed cables,fibers, steel fibers, mineral fibers, synthetic fibers, carbon fibers,steel wire fibers, mesh, lath, and the like.

The preferred cementitious material for use with the present inventioncomprises portland cement. The cementitious material preferablycomprises a reduced amount of portland cement and an increased amount ofsupplementary cementitious materials; i.e., hyaloclastite, sideromelane,tachylite or mixtures thereof in accordance with the present invention.This results in cementitious material and concrete that is moreenvironmentally friendly. The portland cement can also be replaced, inwhole or in part, by one or more pozzolanic materials. Portland cementis a hydraulic cement. Hydraulic cements harden because of a hydrationprocess; i.e., a chemical reaction between the anhydrous cement powderand water. Thus, hydraulic cements can harden underwater or whenconstantly exposed to wet weather. The chemical reaction results inhydrates that are substantially water-insoluble and so are quite durablein water. Other hydraulic cements useful in the present inventioninclude, but are not limited to, calcium aluminate cement, belite cement(dicalcium silicate), phosphate cements and anhydrous gypsum. However,the preferred hydraulic cement is portland cement.

In a disclosed embodiment of the present invention, concrete or mortarcomprises a hydraulic cement, hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention, aggregate andwater. Preferably, the cementitious material used to form the concreteor mortar comprises portland cement and hyaloclastite, sideromelane,tachylite or mixtures thereof powder, more preferably portland cementand hyaloclastite, sideromelane, tachylite or mixtures thereof having avolume-based mean particle size of less than or equal to approximately40 μm, most preferably portland cement and hyaloclastite, sideromelane,tachylite or mixtures thereof having a volume average particle size ofless than or equal to approximately 20 μm, especially less than or equalto approximately 15 μm, more especially less than or equal toapproximately 10 μm, most especially less than or equal to approximately5 μm. The foregoing ranges include all of the intermediate values. Insimple terms, the hyaloclastite, sideromelane, tachylite or mixturesthereof is reduced to a fine powder such that the fine powder haspozzolanic properties.

In another disclosed embodiment of the present invention, concreteincluding hyaloclastite, sideromelane, tachylite or mixtures thereof inaccordance with the present invention can include any other pozzolan incombination with hydraulic cement.

The portland cement and hyaloclastite, sideromelane, tachylite ormixtures thereof in accordance with the present invention can becombined physically or mechanically in any suitable manner and is not acritical feature of the present invention. For example, the portlandcement and hyaloclastite, sideromelane, tachylite or mixtures thereof inaccordance with the present invention can be mixed together to form auniform blend of dry cementitious material prior to combining with theaggregate and water. Or, the portland cement and hyaloclastite,sideromelane, tachylite or mixtures thereof in accordance with thepresent invention can be added separately to a conventional concretemixer, such as a transit mixer of a ready-mix concrete truck, at a batchplant. The water and aggregate can be added to the mixer before thecementitious material; however, it is preferable to add the cementitiousmaterial first, the water second, the aggregate third and any makeupwater last.

Chemical admixtures can also be used with the concrete in accordancewith the present invention. Such chemical admixtures include, but arenot limited to, accelerators, retarders, air entrainments, plasticizers,superplasticizers, coloring pigments, corrosion inhibitors, bondingagents and pumping aid.

Mineral admixtures can also be used with the concrete in accordance withthe present invention. Although mineral admixtures can be used with theconcrete of the present invention, it is believed that mineraladmixtures are not necessary. However, in some embodiments it may bedesirable to include a water reducing admixture, such as asuperplasticizer.

Concrete can also be made from a combination of portland cement andpozzolanic material or from pozzolanic material alone. There are anumber of pozzolans that historically have been used in concrete. Apozzolan is a siliceous or siliceous and aluminous material which, initself, possesses little or no cementitious value but which will, infinely divided form and in the presence of water, react chemically withcalcium hydroxide at ordinary temperatures to form compounds possessingcementitious properties (ASTM C618). The broad definition of a pozzolanimparts no bearing on the origin of the material, only on its capabilityof reacting with calcium hydroxide and water. The general definition ofa pozzolan embraces a large number of materials, which vary widely interms of origin, composition and properties The most commonly usedpozzolans today are industrial by-products, such as slag cement (groundgranulated blast furnace slag), fly ash, silica fume from siliconsmelting, and natural pozzolans such as highly reactive metakaolin, andburned organic matter residues rich in silica, such as rice husk ash.

Hyaloclastite, sideromelane and tachylite in accordance with the presentinvention are previously unknown natural pozzolans. They can be used asa substitute for any other pozzolan or in combination with any one ormore pozzolans that are used in combination with any hydraulic cementused to make concrete or mortar.

It is specifically contemplated as a part of the present invention thatconcrete formulations including hyaloclastite, sideromelane, tachyliteor mixtures thereof in accordance with the present invention can be usedwith concrete forms or systems that retain the heat of hydration toaccelerate the curing of the concrete. Therefore, in another disclosedembodiment of the present invention, concrete in accordance with thepresent invention can be cured using concrete forms such as disclosed inU.S. Pat. Nos. 8,555,583; 8,756,890; 8,555,584; 8,532,815; 8,877,329;9,458,637; 8,844,227 and 9,074,379 (the disclosures of which are allincorporated herein by reference); published patent applicationPublication Nos. 2014/0333010; 2014/0333004 and 2015/0069647 (thedisclosures of which are all incorporated herein by reference) and U.S.patent application Ser. No. 15/418,937 filed Jan. 30, 2017 (thedisclosure of which is incorporated herein by reference).

The following examples are illustrative of selected embodiments of thepresent invention and are not intended to limit the scope of theinvention.

Example 1

The hyaloclastite, sideromelane and tachylite in accordance with thepresent invention all have the unexpected property of reduced waterdemand of the cementitious matrix. For example, the water demand ofother pozzolans is higher. As an example, metakaolin's water demand isgreater than portland cement when tested in accordance to ASTM C-618;i.e., water requirement as a percent of control is greater than 100. Asshown in Table 1 below, pumice (a natural pozzolan) and comparableparticle size to hyaloclastite in accordance with the resent inventionhad a water demand greater than portland cement. However, hyaloclastitein accordance with the present invention and having a mean particle sizeof 14 μm when tested in accordance with the ASTM C 311 and ASTM C-618had a water requirement of 97% when compared with the portland cementcontrol sample. The hyaloclastite in accordance with the presentinvention of mean particle size of 8 μm when tested in accordance withthe ASTM C-618 had a water requirement of 96% when compared with theportland cement control sample. The hyaloclastite in accordance with thepresent invention having a mean particle size of 4 μm when tested inaccordance with the ASTM C-618 had a water requirement of 97% whencompared with the portland cement control sample. When tested inaccordance to ASTM-618 the hyaloclastite had significantly lower waterdemand than pumice or portland cement. The water demand of each type isshow in Table 1 below.

TABLE 1 ASTM C-618 Water requirement test results compared to controlsample SiO₂ Al₂O₃ Fe₂O₃ Total (SiO₂ + Water Requirement Product type (%)(%) (%) Al₂O₃ + Fe₂O₃) (Test H₂O/Control H₂O) Pumice (14 μm, d50) 64.3015.17 7.89 87.36 103%  Hyaloclastite (14 μm, d50) 46.99 12.15 12.1371.28 97% Pumice (8 μm, d50) 63.57 15.23 7.82 86.62 103%  Hyaloclastite(8 μm, d50) 47.20 12.49 12.04 71.73 95% Hyaloclastite (4 μm, d50) 47.2012.49 12.04 71.73 97%

Example 2

Hyaloclastite, sideromelane and tachylite in accordance with the presentinvention all have the unexpected property of significantly reducing ASRin concrete. Test specimens were prepared in accordance with theprocedures described in ASTM C441 as modified by ASTM C311. Threecontrol mortar bars were each prepared from a control mix and three testmortar bars were each prepared from a test mix using the modifiedproportions specified by ASTM C311. The mix proportions are listed inTable 2 below.

TABLE 2 Mix Proportions Control Mix Test Mix Cemex Cement, g 400 0Lehigh Cement, g 0 300 Hyaloclastite (8 μm, d50), g 0 100 Graded PyrexGlass, g 900 900 Water, ml 226 213 Flow (100-115%) 115 102

As required by ASTM C311, the cement for the control mixture had analkali content less than 0.60% (as equivalent Na₂O) and the cement usedin the test mixture had an alkali content greater than that of thecement used in the control mixture. Cemex cement with an equivalent Na₂Oof 0.30% was used for the control mixtures and Lehigh cement with anequivalent Na₂O of 0.61% was used for the test mixture. A sufficientamount of water was used to produce a flow of 100% to 115%. Thespecimens were cured in a moist room for 24 hours and then stored in amoist container as specified in ASTM C227-10 Standard Test Method forPotential Alkali Reactivity of Cement-Aggregate Combinations (Mortar-BarMethod) at 38° C.±2° C. for 14 days. Results of the testing are reportedin Table 3 below.

TABLE 3 ASR Test Results Length (inches) Length Initial 14 Days Change(%) Control 1 0.0463 0.0487 0.022 Control 2 0.0528 0.0546 0.016 Control3 0.0542 0.0439 0.018 Average 0.019 Longview 1 0.0464 0.0463 −0.003Longview 2 0.0456 0.0452 −0.006 Longview 3 0.0443 0.0439 −0.006Reference 0.0436 0.0438 — Average −0.005 Reduction of Mortar Expansionas % of Control 126.3%

When tested in accordance to the ASTM C441-11, the test bars showed areduction of Mortar Bar Expansion of 126.3% when compared to the controlbar. Typical Fly Ash Mortar Bar Expansion reduction when tested inaccordance with ASTM C441-11 is approximately 60%-75%. Thus,hyaloclastite in accordance with the present invention reduces ASR muchbetter than fly ash.

Example 3

Hyaloclastite, sideromelane and tachylite in accordance with the presentinvention all have the unexpected property of improved strengthdevelopment. Test specimens were prepared in accordance with theprocedures described in ASTM C311 and tested in accordance with ASTMC618. Control mortar samples were each prepared from a control mix andmortar samples of pumice of 14 μm and 8 μm average mean particle sizeand hyaloclastite of 14 μm, 8 μm and 4 μm average mean particle size inaccordance with the present invention. These mortar cubes samples wereeach prepared from a test mix using the modified proportions specifiedby ASTM C311 and tested in accordance with ASTM C618. Sufficient sampleswe made and testing was conducted at 1, 3, 7, 14, 28 and 56 days. Inorder to pass ASTM C618, a natural pozzolan must have a minimum of 75%strength gain at 7 and 28 days when compared to the portland cementsample. As shown below, hyaloclastite in accordance with the presentinvention performed better than pumice at each of these intervals.Surprisingly, while pumice at 8 μm mean particle size developed lowercompressive strength than pumice at 14 μm mean particle size; whereas,hyaloclastite at 8 μm mean particle size developed higher compressivestrength than hyaloclastite at 14 μm mean particle size. Over timehyaloclastite in accordance with the present invention had similar orbetter compressive strength test results than the portland cementcontrol samples. Results are of these tests are shown in Tables 4 and 5below.

TABLE 4 ASTM C-618 Mortar Cube Testing results Compression PSI ControlControl Control Pumice Pumice Hyaloclastite Hyaloclastite HyaloclastiteTest #1 #2 #3 (14 μm, d50) (8 μm, d50) (14 μm, d50) (8 μm, d50) (4 μm,d50)  1 Day 2850 2980 2170 2450 2510 2620  3 Day 4840 4610 3300 36203710 4160  7 Day 4680 5150 3750 3360 3960 4240 5060 14 Day 5520 56304430 4130 4770 5760 28 Day 5640 6350 5180 4610 5280 5530 7030 56 Day6410 6060 5540 5570 5700 6670

TABLE 5 Percentage strength gain (test sample/control sample) SAI %Pumice Pumice Hyaloclastite Hyaloclastite Hyaloclastite (14 μm, (8 μm,(14 μm, (8 μm, (4 μm, Test d50) d50) d50) d50) d50)  1 Day 76 82 84 88 3 Day 68 79 80 90  7 Day 80 72 85 91 98 14 Day 80 73 85 102 28 Day 9282 94 98 111 56 Day 86 92 94 110

The foregoing tests demonstrate that hyaloclastite in accordance withthe present invention unexpectedly produces greater compressive strengthgain than pumice (a natural pozzolan) and the portland cement controlsamples.

Example 4

The specific gravity of portland cement is 3.1. The specific gravity ofpozzolans varies from 2.05 to 2.65. Table 6 below shows the specificgravity for portland cement, hyaloclastite, pumice, dacite, rhyolite,fly ash, matakaolin and nano silica.

TABLE 6 Specific Gravity comparison Product type Specific GravityPortland Cement 3.10 Hyaloclastite 2.8-3.0 Pumice 2.3-2.6 Dacite 2.6-2.7Rhyolite 2.7-2.8 Fly Ash 2.03-2.6  Metakaolin 2.5-2.6 Nanosilioca 2.20

When pozzolans are used to replace portland cement, the ratio ofreplacement takes into consideration specific gravity. Since allpozzolans have a lower specific gravity than portland cement, thepozzolan's replacement weight must be adjusted according to thedifference in the density. Accordingly, known pozzolan replacementratios are often greater than 1 and sometimes as high as 1.3.Hyaloclastite in accordance with the present invention has a specificgravity of 2.90-3.0. Therefore, the replacement ratio of hyaloclastitein accordance with the present invention for portland cement can beone-to-one, thereby saving material and costs.

Example 5

The particle size of hyaloclastite in accordance with the presentinvention was analyzed using a MICROTRAC—X100 light scattering particlessize measuring equipment. The particles were measure in isopropylalcohol, had a reflective index of 1.38, a load factor of 0.0824 and atransmission of 0.87. Table 7 below shows a summary of the particlessize analysis for a hyaloclastite sample wherein 85% by volume of theparticles passed through a 325-mesh screen.

TABLE 7 Property Value mv 15.10 mn 1.180 ma 4.651 cs 1.290 sd 12.62

In Table 7 above, the abbreviation “my” means “mean diameter in micronsof the “volume distribution” represents the center of gravity of thedistribution. Mie or modified Mie calculations are used to calculate thedistribution. Implementation of the equation used to calculate MV willshow it to be weighted (strongly influenced) by a change in the volumeamount of large particles in the distribution. It is one type of averageparticle size or central tendency”.

The abbreviation “mn” means “mean diameter, in microns, of the “numberdistribution” is calculated using the volume distribution data and isweighted to the smaller particles in the distribution. This type ofaverage is related to population or counting of particles”.

The abbreviation “ma” means “mean diameter, in microns, of the “areadistribution” is calculated from the volume distribution. This area meanis a type average that is less weighted (also less sensitive) than theMV to changes in the amount of coarse particles in the distribution. Itrepresents information on the distribution of surface area of theparticles of the distribution”.

The abbreviation “cs” means “calculated surface—Provided in units ofM²/cc, the value provides an indication of the specific surface area.The CS computation assumes smooth, solid, spherical particles. It may beconverted to classical units for SSA of M²/g by dividing the value bythe density of the particles. It should not be interchanged with BET orother adsorption methods of surface area measurement since CS does nottake into effect porosity of particles, adsorption specificity ortopographical characteristics of particles”.

The abbreviation “cs” means “Standard Deviation in microns, also knownas the Graphic Standard Deviation (σ_(g)), is one measure of the widthof the distribution. It is not an indication of variability for multiplemeasurements. Equation to calculate is: (84%−16%)/2”.

In Table 8 below, the particle size distribution is shown in terms ofpercentile.

TABLE 8 Percentile Value 10% 1.735 20% 3.047 30% 4.638 40% 6.707 50%9.393 60% 13.11 70% 17.92 80% 24.27 90% 35.31 95% 47.68

In Table 9 below, the particle size distribution is shown in terms ofparticle size.

TABLE 9 Size (microns) % Pass 704.0-104.7 100.00 95.96 99.74 88.00 99.3680.70 98.99 74.00 98.58 67.86 98.10 62.23 97.54 52.33 96.06 57.06 96.8747.98 95.08 44.00 93.92 40.35 92.55 37.00 90.96 33.93 89.13 31.11 87.0728.53 84.79 26.16 82.31 23.99 79.65 22.00 76.85 20.17 73.97 18.50 71.0716.96 68.18 15.56 65.35 14.27 62.60 13.08 59.92 12.00 57.30 11.00 54.7110.09 52.13 9.250 49.55 8.482 46.96 7.778 44.37 7.133 41.80 6.541 36.835.998 36.83 5.500 34.45 5.044 32.15 4.625 29.93 4.241 27.76 3.889 25.653.566 23.58 3.270 21.58 2.999 19.66 2.750 17.83 2.522 16.12 2.312 14.542.121 13.08 1.945 11.71 1.783 10.41 1.635 9.15 1.499 7.91 1.375 6.691.261 5.49 1.156 4.36 1.060 3.33 0.972 2.44 0.892 1.72 0.818 1.15 0.7500.73 0.688 0.41 0.630 0.16 0.578-0.133 0.00

Example 6

The particle size of hyaloclastite in accordance with the presentinvention was analyzed using a MICROTRAC—X100 light scattering particlessize measuring equipment. The particles were measure in isopropylalcohol, had a reflective index of 1.38, a load factor of 0.0884 and atransmission of 0.86. Table 10 below shows a summary of the particlessize analysis for a hyaloclastite sample wherein 95% by volume of theparticles passed through a 325-mesh screen.

TABLE 10 Property Value mv 8.736 mn 1.488 ma 4.386 cs 1.368 sd 6.136

In Table 11 below, the particle size distribution is shown in terms ofpercentile.

TABLE 11 Percentile Value 10% 1.953 20% 2.962 30% 3.987 40% 5.270 50%6.830 60% 8.682 70% 10.74 80% 13.44 90% 17.74 95% 22.21

Table 12 below, the particle size distribution is shown in terms ofparticle size.

TABLE 12 Size (microns) % Pass 704.0-52.33 100.00 47.98 99.87 44.0099.68 40.35 99.46 37.00 99.20 33.93 98.86 31.11 98.43 28.53 97.87 26.1697.12 23.99 96.13 22.00 94.85 20.17 93.21 18.50 91.16 16.96 88.66 15.5685.75 14.27 82.46 13.08 78.86 12.00 75.05 11.00 71.11 10.09 67.12 9.25063.15 8.482 59.25 7.778 55.45 7.133 51.78 6.541 48.25 5.998 44.86 5.50041.58 5.044 38.39 4.625 35.27 4.241 32.18 3.889 29.13 3.566 26.11 3.27023.18 2.999 20.39 2.750 17.80 2.522 15.46 2.312 13.38 2.121 11.55 1.9459.93 1.783 8.48 1.635 7.15 1.499 5.91 1.375 4.76 1.261 3.69 1.156 2.731.060 1.92 0.972 1.26 0.892 0.77 0.818 0.41 0.750 0.15 0.688-0.133 0.00

In another disclosed embodiment of the present invention, hyaloclastite,sideromelane, or tachylite or mixtures thereof, in accordance with thepresent invention, can be used to form a geopolymer-based cementitiousbinder; specifically, geopolymer cement or geopolymer cement concrete.To form a geopolymer cement, hyaloclastite, sideromelane, tachylite orcombinations or mixtures thereof in accordance with the presentinvention; i.e., having the desired particle sizes as specified above,is combined with an aqueous alkaline activating solution.

In geopolymer formation an aluminosilicate material is mixed with anaqueous alkaline activating solution that initially dissolves aluminumand silicon ion from the hyaloclastite, sideromelane or tachylitethereby releasing silica and alumina monomers. The degree to which thealuminosilicate material dissolves is related to the reactivity of thematerial, the strength of the activating solution and time. Alkalineactivating solutions are typically an alkaline soda, such as sodiumhydroxide or potassium hydroxide, and optionally an aqueous solublesilica, such as sodium silicate or potassium silicate. The concentrationof effective alkaline activating solutions typically ranges fromapproximately 1.7 to 3.3 lbs (5 to 10 N) hydroxide per gallon ofsolution. The alumina and silica monomers then begin to reorganize andcondense into larger groups. As the groups form, water molecules arereleased. The dissolution phase and the alkalinity of the activatingsolution greatly affect the rate of reaction.

In a disclosed embodiment of the present invention, it is desirable tobalance the amount of Si, Al and water in a geopolymer cement concretemix design. Then using a hyaloclastite, sideromelane, tachylite pozzolanin accordance with the present invention, the amount of Si and Al mayvary depending on the source of the hyaloclastite, sideromelane,tachylite. For example, as stated above hyaloclastite from a basalticsource will have less than 53% by weight SiO₂; whereas, hyaloclastitefrom a rhyolitic source has greater than 69% by weight SiO₂. It is alsodesirable to balance the amount of water and activating agent. Table 13below shows desirable ratios of the foregoing agents for a preferredgeopolymer cement concrete.

TABLE 13 Compositional Ranges Ratio Ranges (by weight) Materials LowHigh M₂O/SiO₂ 0.2 0.48 SiO₂/Al₂O₃ 3.3 4.5 H₂O/M₂O 10.0 25.0 M₂O/Al₂O₃0.8 1.6

In Table 13 above, M represents Na or K. In general, K provides morestrength, but is usually more expensive than Na. Additions of CaO orCaCO₃ tend to improve strength. If setting times are too fast, thenborate can be added as a retarder which may result in strength increase.

Alkaline activating solutions useful in the present invention compriseaqueous solutions of compounds having reactive hydroxyl groups, such ashydroxides, and optionally water-soluble alkali metal silicates ormixtures thereof. Alkaline activating agents include, but are notlimited to, NaOH (lye), KOH, CaOH (hydrate lime), or other minerals orcompounds having reactive hydroxyl groups. Particularly preferredhydroxides are NaOH and KOH. Of course, the hydroxide can be generatedin situ be adding in dry form Na₂O, K₂O or CaO (quick lime), which uponhydration yields NaOH, KOH and CaOH, respectively. It is sometimesdesirable to provide the natural pozzolan of the present invention andthe alkaline activating agent as a premix in dry form. The dry premixcan then be combined with water to form the geopolymer cement.

The optional water-soluble alkali metal silicates include, but are notlimited to, sodium silicates, potassium silicates and aluminosilicates.Sodium silicate is a generic name for chemical compounds with theformula Na_(2x)Si_(y)O_(2y+x) or (Na₂O)_(x).(SiO₂)_(y), such as sodiummetasilicate Na₂SiO₃, sodium orthosilicate Na₄SiO₄ and sodiumpyrosilicate Na₆Si₂O₇. The anions are often polymeric. These compoundsare generally colorless, transparent solids or white powders and aresoluble in water in various amounts. Because geopolymer cement curingdoes not rely on hydration reactions, it is particularly attractive forits rapid strength development and reduced tendency for shrinkage andcreep compared with portland cement.

Additionally, a relatively small amount of hydraulic cement or pozzolancan be used as a component of the alkaline activating solution. Amountsof hydraulic cement or pozzolan can be used alone or in combination withthe alkaline activating agents listed above. Amounts of hydraulic cementor pozzolan can be used up to and including 30% by weight of thegeopolymer; i.e., 0% to 30% by weight (the foregoing range includes allof the intermediate values). A preferred hydraulic cement for use in thepresent invention is kiln dust, a waste product of the portland cementmanufacture may be used to create an alkaline environment. Pozzolansthat can be used in the present invention include, but are not limitedto, industrial by-products, such as slag cement (ground granulated blastfurnace slag), fly ash, silica fume from silicon smelting, and naturalpozzolans such as highly reactive metakaolin, and burned organic matterresidues rich in silica, such as rice husk ash.

Geopolymer cement is an alternative to portland cement. Advantages ofgeopolymer cement include, but are not limited to, resistance to freezeand thaw cycling, high chemical resistance, faster or slower set timeswhich are formulation controllable, low air and water permeability andheat resistance. Significantly, geopolymer cement provides environmentalbenefits due to its reduced carbon footprint.

Mixing and curing temperatures are factors that affect the physicalcharacteristics of geopolymer cement and concrete. Curing at highertemperatures generally accelerates curing and strength gain.Accordingly, self-annealing concrete forms can be used to accelerate thecuring of geopolymer cements and concretes in accordance with thepresent invention. Self-annealing concrete forms that can be used withthe geopolymer cements and concrete of the present invention include,but are not limited to, the forms disclosed in U.S. Pat. Nos. 8,555,583;8,756,890; 8,555,584; 8,532,815; 8,844,227; 8,877,329; 9,074,379;9,458,637; 9,776,920; 9,862,118; 10,065,339; 10,220,542; and 10,280,622(the disclosures of which are all incorporated herein by reference intheir entirety).

In a disclosed embodiment of the present invention, hyaloclastite havinga particle size of less than or equal to 40 microns, preferably lessthan or equal to 20 microns, more preferably less than or equal to 10microns, especially less than or equal to 5 microns (all volume-basedmean particle size), is combined with an alkaline activating solution.The alkaline activating solution is sodium hydroxide and optionallysodium silicate dissolved in water. Alternatively, the alkalineactivating solution is potassium hydroxide and optionally potassiumsilicate dissolved in water. To make a geopolymer cement in accordancewith the present invention, the hyaloclastite powder and the alkalineactivating solution are combined. To make a geopolymer cement concretein accordance with the present invention, the hyaloclastite powder andaggregate (fine aggregate, coarse aggregate or both) are combined withthe alkaline activating solution.

The following examples are illustrative of selected embodiments of thepresent invention and are not intended to limit the scope of theinvention.

Example 7

Geopolymer cement concrete is formed by combining the constituents shownin Table 14 below.

TABLE 14 Material Weight (lbs/yd³) Sodium silicate 277 Sodium hydroxide36 Hyaloclastite (8 micron) 787 Fine aggregate 1370 Coarse aggregate1370 Water 75 Total 3915

The geopolymer cement concrete is cured at a temperature of 140 to 170°F. (60 to 77° C.). The resulting cured geopolymer cement concrete hasphysical properties comparable to or better than portland cementconcrete.

Example 8

Geopolymer cement concrete is formed by combining the constituents shownin Table 15 below.

TABLE 15 Material Weight (lbs/yd³) potassium silicate 277 potassiumhydroxide 36 Sideromelane (4 micron) 787 Water 75 Fine aggregate 1370Coarse aggregate 1370 Total 3915

The geopolymer cement concrete is cured at a temperature of 140 to 170°F. (60 to 77° C.). The resulting cured geopolymer cement has physicalproperties comparable to or better than portland cement concrete.

Example 9

Geopolymer cement concrete is formed by combining the constituents shownin Table 16 below.

TABLE 16 Material Weight (lbs/yd³) potassium silicate 277 sodiumhydroxide 36 Tachylite (8 micron) 787 Water 75 Fine aggregate 1370Coarse aggregate 1370 Total 3915

The geopolymer cement concrete is cured at a temperature of 140 to 170°F. (60 to 77° C.). The resulting cured geopolymer cement has physicalproperties comparable to or better than portland cement concrete.

Example 10

Geopolymer cement concrete is formed by combining the constituents shownin Table 17 below.

TABLE 17 Material Weight (lbs/yd³) sodium silicate 277 potassiumhydroxide 36 Hyaloclastite (4 micron) 787 Water 75 Fine aggregate 1370Coarse aggregate 1370 Total 3915

The geopolymer cement is cured at ambient or elevated temperatures. Theresulting cured geopolymer cement has physical properties comparable toor better than portland cement concrete.

Example 11

Geopolymer cement concrete is formed by combining the constituents shownin Table 18 below. A water reducing admixture can be added to the mixsuch as ADVA190 from Grace, Columbia, Md.

TABLE 18 Mixture Proportions Batch Proportions Solid SSD SSD ActualVolume Batch Batch Corr. Batch Material one m³ Mass (kg) Wt. (lb) (lb)Wt. (lb) Hyaloclastite 0.1851 409 89.4 0.000 89.4 ACM Sand 0.2242 590128.8 −1.5 130.3 Pea Gravel 0.4552 1256 274.5 5.0 269.5 Na₂SiO₃ 0.0670103 22.4 22.40 NaOH 0.0260 41 8.9 8.86 L kg fl. oz lb ml Adva 190 5.56.0 18.5 1.30 547 Water 0.0225 22.5 4.9 3.5 8.44 Air 0.02 admix 8.44adjusted Yield 1 1 Final Water 8.44

Example 12

Geopolymer cement concrete is formed by combining the constituents shownin Table 19 below.

TABLE 19 Material Weight (lbs/yd³) sodium silicate 277 potassiumhydroxide 18 Kiln dust 18 Hyaloclastite (4 micron) 787 Water 75 Fineaggregate 1370 Coarse aggregate 1370 Total 3915

The geopolymer cement is cured at ambient or elevated temperatures. Theresulting cured geopolymer cement has physical properties comparable toor better than portland cement concrete.

Example 13

Geopolymer cement concrete is formed by combining the constituents shownin Table 20 below.

TABLE 20 Material Weight (lbs/yd³) sodium silicate 277 potassiumhydroxide 18 Portland cement 18 Hyaloclastite (4 micron) 787 Water 75Fine aggregate 1370 Coarse aggregate 1370 Total 3915

The geopolymer cement is cured at ambient temperature or elevatedtemperatures. The resulting cured geopolymer cement has physicalproperties comparable to or better than portland cement concrete.

Example 14

Geopolymer cement concrete is formed by combining the constituents shownin Table 21 below.

TABLE 21 Material Weight (lbs/yd³) sodium silicate 277 potassiumhydroxide 18 Portland cement 18 tachylite (4 micron) 787 Water 75 Fineaggregate 1370 Coarse aggregate 1370 Total 3915

The geopolymer cement is cured at ambient temperature or elevatedtemperatures. The resulting cured geopolymer cement has physicalproperties comparable to or better than portland cement concrete.

Example 15

Geopolymer cement concrete is formed by combining the constituents shownin Table 22 below.

TABLE 22 Material Weight (lbs/yd³) sodium silicate 277 potassiumhydroxide 18 Portland cement 18 sideromelane (4 micron) 787 Water 75Fine aggregate 1370 Coarse aggregate 1370 Total 3915

The geopolymer cement is cured at ambient temperature or elevatedtemperatures. The resulting cured geopolymer cement has physicalproperties comparable to or better than portland cement concrete.

Example 16

Geopolymer cement concrete is formed by combining the constituents shownin Tables 23 and 24 below.

TABLE 23 Material kg/cu m Sp. G Volume Hyaloclastite Pozzolan 390 2.83137.81 Silica Sand 550 2.26 243.36 Coarse Agg Granite 1320 2.8 471.43NaOH (40%) 40 1.5 26.67 Na2SiO3 100 1.53 65.36 Water 40 1 40 Super(polycarboxylate) 5.9 1.08 5.46 Air(1%) 10 1000

The mix shown in Table 23 above translates into a mix by weight as shownin Table 24 below.

TABLE 24 Material lb/cu yd Hyaloclastite Pozzolan 659 Silica Sand 930Coarse Agg Granite 2231 NaOH (40%) 68 Na₂SiO₃ 169 Water 68 Super 10

The geopolymer cement is cured at ambient or elevated temperatures. Theresulting cured geopolymer cement has physical properties comparable toor better than portland cement concrete.

Of course, conventional concrete admixtures, such as water reducers, canbe added to the geopolymer cement concrete formulations in accordancewith the present invention.

It should be understood, of course, that the foregoing relates only tocertain disclosed embodiments of the present invention and that numerousmodifications or alterations may be made therein without departing fromthe spirit and scope of the invention as set forth in the appendedclaims.

1. A cementitious material comprising: a natural pozzolan selected fromhyaloclastite, sideromelane, tachylite or combinations or mixturesthereof, wherein the natural pozzolan has a volume-based mean particlesize of less than or equal to approximately 40 μm; and an aqueousalkaline activating solution suitable for forming a geopolymer.
 2. Thecementitious material of claim 1, wherein the natural pozzolan has avolume-based mean particle size of less than or equal to approximately20 μm.
 3. The cementitious material of claim 1, wherein the naturalpozzolan has a volume-based mean particle size of less than or equal toapproximately 10 μm.
 4. The cementitious material of claim 1, whereinthe natural pozzolan has a volume-based mean particle size of less thanor equal to approximately 5 μm.
 5. The cementitious material of claim 1,wherein the aqueous alkaline activating solution comprises a hydroxideselected from NaOH, KOH, CaOH, and other minerals or compounds havingreactive hydroxyl groups.
 6. The cementitious material of claim 5,wherein the hydroxide is sodium hydroxide or potassium hydroxide.
 7. Thecementitious material of claim 5, wherein the aqueous alkalineactivating solution further comprises a water-soluble alkali metalsilicate.
 8. The cementitious material of claim 7, wherein thewater-soluble alkali metal silicate is sodium silicate or potassiumsilicate.
 9. The cementitious material of claim 1, wherein the aqueousalkaline activating solution comprises sodium hydroxide or potassiumhydroxide and sodium silicate or potassium silicate.
 10. Thecementitious material of claim 1 further comprising aggregate.
 11. Acementitious-based material comprising: aggregate; hyaloclastite havinga volume-based mean particle size of less than or equal to approximately40 μm; and an alkaline activating solution comprising: sodium hydroxideor potassium hydroxide; and water.
 12. The cementitious-based materialof claim 11, wherein the natural pozzolan has a volume-based meanparticle size of less than or equal to approximately 20 μm.
 13. Thecementitious-based material of claim 11, wherein the natural pozzolanhas a volume-based mean particle size of less than or equal toapproximately 10 μm.
 14. The cementitious-based material of claim 11,wherein the natural pozzolan has a volume volume-based mean size of lessthan or equal to approximately 5 μm.
 15. The cementitious-based materialof claim 11 further comprising a water-soluble alkali metal silicate.16. The cementitious-based material of claim 15, wherein thewater-soluble alkali metal silicate is sodium silicate or potassiumsilicate.
 17. A cementitious-based material comprising: aggregate;hyaloclastite having a volume-based mean particle size of less than orequal to approximately 40 μm; and an alkaline activating solutionsuitable for forming a geopolymer comprising: a compound having areactive hydroxyl group; and water.
 18. (canceled)
 19. Thecementitious-based material of claim 17, wherein the compound having areactive hydroxyl group is NaOH, KOH or CaOH.
 20. The cementitious-basedmaterial of claim 19, wherein the natural pozzolan has a volume-basedmean particle size of less than or equal to approximately 20 μm.
 21. Thecementitious-based material of claim 19, wherein the natural pozzolanhas a volume-based mean particle size of less than or equal toapproximately 10 μm.